The present invention relates to apparatus for the television scanning of films.
Apparatus for scanning a film in a line-by-line manner to enable the film to be shown on television has already been proposed in German OS No. 27 35 685 to which U.S. Pat. No. 4,288,818, POETSCH, assigned to the assignee of this application, corresponds. An improved version of that apparatus is disclosed in German Patent Application P No. 2921934 which is the subject of United States Patent Application Ser. No. 061,151,781, filed May 21, 1980, now U.S. Pat. No. 4,310,856 to Dieter Poetsch, assigned to the assignee of this application.
Two disadvantages of the apparatus described in the above reference U.S. Pat. No. 4,310,856 have been discovered. The first is that during the so-called uncoupled operation of the film scanner, that is when the film is running asynchronously with respect to a television studio clock signal at a speed of less than 50 frames per second, the reproduced television picture has a horizontally extending cut edge. Due to this interfering cut edge, the television picture is divided into two regions wherein the lower portion still includes information from the preceding film frame.
The second disadvantage is that during the scanning of 35 mm Cinemascope films, in which the frame line of the film is known to be narrower than the V-blanking intervals of the television picture, the reproduced television picture has a horizontally extending cut edge. The television picture is divided into two regions by this interfering cut edge wherein the lower portion still contains information from the preceding film frame.